/*
 * Copyright (c) 2013, 2017, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package com.oracle.svm.core.heap;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.util.function.BooleanSupplier;

import org.graalvm.nativeimage.Platform;
import org.graalvm.nativeimage.Platforms;

/**
 * For fields with this annotation no static analysis is done.
 *
 * It is assumed that a field of type c may hold a reference to any subtype of c. It is also assumed
 * that any subtype of c is instantiated.
 *
 * This annotation is only necessary during the image build. It prevents the static analysis from
 * wrongly constant-folding a value that is initialized late during the image build and therefore
 * not available during analysis.
 */
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.FIELD)
@Platforms(Platform.HOSTED_ONLY.class)
public @interface UnknownObjectField {

    /**
     * Specify types that this field can take.
     */
    Class<?>[] types() default {};

    /**
     * Specify fully qualified names of types that this field can take.
     */
    String[] fullyQualifiedTypes() default {};

    /**
     * Specify if this field can be null. By default unknown value object fields cannot be null.
     */
    boolean canBeNull() default false;

    Class<? extends BooleanSupplier> availability();
}
